This article reports a mixed-method research probing the effect of utilizing a blog-buddy system on English for academic purposes learners' writing performance. Sixty Iranian undergraduate engineering students at Iran University of Science and Technology Virtual Campus participated in this study. Our analysis of the students' writings indicated that blog-integrated writing instruction accompanied with the implementation of a blog-buddy system resulted in a significant improvement in students' writing performance. Further, the results of an attitudinal survey revealed that students who received feedback from blog-buddies showed higher positive attitudes toward utilizing blogs for their writing classes. For further investigation, data were gathered through comments the participants left on the weblog and the forums, semistructured interviews, and teacher observations. Four themes emerged, which were used to come up with a framework based on the learner-centred approach. The framework integrates web-based trainings and learners' learning styles and fosters the learners' control of their learning experiences.